• 방송공학회논문지
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• 제16권4호
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• pp.680-683
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• 2011

본 논문에서는 레일리 페이딩 채널에서 대표적인 3차원 신호성상도들의 이론적인 심볼오류확률을 유도한다. 모의실험을 통하여 제시된 평균 심볼오류확률이 매우 정확함을 검증하였다. 따라서 유도된 이론적 심볼오류확률은 향후 3차원 신호성상도를 이용하는 무선 통신시스템의 개발을 위한 성능 기준으로 활용할 수 있을 것으로 판단된다.

• 조명전기설비학회논문지
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• 제24권12호
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• pp.138-146
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• 2010

On wind turbine generators, the speed and volume of the wind affect the turbine angle speed which finally determines the output level of the electric power. However it is very difficult to forecast correctly the future power output and quality based on previous fixed sampling methods. This paper proposes a variable sampling method based on Buneman frequency estimation algorithm to reflect the variations of the frequency and amplitude on wind power outputs. The proposed method is also verified through the performance test by comparing with the results from previous fixed sampling methods and the real measurement data.

• 한국해양공학회지
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• 제32권1호
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• pp.62-67
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• 2018

A wave buoy commonly used for measurements in marine environments is very useful for measurements on the sea surface wind and waves. However, it is constantly exposed to external forces such as typhoons and the risk of accidents caused by ships. Therefore, the installation and maintenance charges are large and constant. In this study, we developed a system for monitoring the sea surface wind using marine radar to provide spatial and temporal information about sea surface waves at a small cost. The essential technology required for this system is radar signal processing. This paper also describes the analytical process of using it for monitoring the sea surface wind. Consequently, developing this system will make it possible to replace wave buoys in the near future.

• Journal of information and communication convergence engineering
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• 제13권3호
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• pp.167-171
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• 2015

A radio over fiber (RoF) system is a kind of analog optical transmission system and considered as a strong candidate for the next-generation fronthaul link in the future mobile network. In RoF systems, nonlinearity compensation is essential to increase the link capacity. In this paper, we propose a nonlinearity detection and compensation scheme using a monitoring channel in RoF systems. A monitoring channel is added at the transmitter site and used for transmitting a reference signal in an RoF transmission. The nonlinearity in the RoF transmission is detected by comparing the received monitoring signal and the original reference signal at the receiver site. Finally, the nonlinearity is compensated at the receiver by giving the reverse function of the detected nonlinearity. Our results show that the proposed scheme can almost remove the error vector magnitude degradation induced by the nonlinearity in the RoF system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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• pp.584-587
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• 1997

In this paper, we present a transmission constraints modeling of carrier relay signal over ATM network. Since teleprotection system, which is used for protecting power transmission lines using telecommunications, has strict transmission delay constraints, it is a important problem to transmit teleprotection signals in future utilities' ATM networks when utilites' communications are integrated. Therefore, we considered the transmission constraints of carrier relay signal over ATM network and the transmission model system.

• 융합신호처리학회논문지
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• 제14권4호
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• pp.212-216
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• 2013

As virtual reality technologies are advanced rapidly, how to render 3D objects across modalities is becoming an important issue. This study is therefore aimed to investigate human discriminability on the curvature of 3D polygonal surfaces with focusing on the vision and touch senses because they are most dominant when explore 3D shapes. For the study, we designed a psychophysical experiment using signal detection theory to determine curvature discrimination for three conditions: haptic only, visual only, and both haptic and visual. The results show that there is no statistically significant difference among the conditions although the threshold in the haptic condition is the lowest. The results also indicate that rendering using both visual and haptic channels could degrade the performance of discrimination on a 3D global shape. These results must be considered when a multimodal rendering system is designed in near future.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -3
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• pp.1428-1431
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• 2002

It is general opinion that the future mobile multimedia networks will use different standards and a prospective solution to this problem will be software defined radio (SDR) techniques. SDR provides the flexibility to support multiple air interfaces and signal processing functions at the same time. Especially, digital signal processors and FPGAs are widely used for implementation of these adaptive and flexible functions of a baseband modem for SDR applications. Also, it is known that the modulation schemes of OCQPSK (Orthogonal Complex QPSK) and HPSK (Hybrid PSK) are used for IMT-2000 services of cdma2000 and WCDMA, respectively. Thus, in this paper, we design and implement an OCQPSK / HPSK modem using a DSP chip of Texas Instrument's TMS320C6701. One modulation scheme is operated by adaptive selection between the two schemes and 5 physical traffic channels differentiated by orthogonal codes are implemented in one DSP chip and each channel has 1Mbps data rates and 8Mcps chip rates.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2006년도 하계종합학술대회
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• pp.869-870
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• 2006

In this study, we proposed an algorithm which can detect the walking event in hemiplegic patient using three axis acceleration signal. Twenty hemiplegic patients were participated in an experiment on a level corridor. To evaluate the accuracy, we compared the time difference between the detected event and signal from FSR-Sensor. Consequently, the mean difference of 46.1ms was obtained and it suggests that the proposed method is effective to detect the walking event in hemiplegic patient. In future, these results could be used to evaluate the walking ability in hemiplegic patient in clinical practice.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 ITC-CSCC -1
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• pp.318-321
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• 2000

This paper propose the method of constructing the highly efficiency adder and multiplier systems over finite fie2, degree of uk terms, therefore we decrease k into m-1 degree using irreducible primitive polynomial. We propose two method of control signal generation for perform above decrease process. One method is the combinational logic expression and the other method is universal signal generation. The proposed method of constructing the highly adder/multiplier systems is as following. First of all, we obtain algorithms for addition and multiplication arithmetic operation based on the mathematical properties over finite fields, next we construct basic cell of A-cell and M-cell using T-gate and modP cyclic gate. Finally we construct adder module and multiplier module over finite fields after synthesize ${\alpha}$$\^$k/ generation module and control signal CSt generation module with A-cell and M-cell. Then, we propose the future research and prospects.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 춘계학술대회 논문집
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• pp.473-480
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• 2002

In this paper, it was proposed that hazard analysis and risk assessment about railway signal systems using FTA(Fault Tree Analysis) and ETA(Event Tree Analysis) one of the reliability analysis methods executed and output value based on the hazard baseline of CENELEC and EC 61508 producted, and also the SIL(Safety Integrity Level)/THR(Tolerable Hazard Rate) about the system set. On the basis of this principle, more systematic standardizations are required to operate railway system and in the future, we hope that safety and reliability of signal equipment will be better improved.